kernel/linux.git/drivers/i2c/muxes, branch v7.2-rc5

i2c: mux: reg: use device property accessors

2026-06-09T11:00:33+00:00

Convert the device-tree parsing path to the generic fwnode/device property accessors so the driver can be probed on ACPI and swnode platforms as well as OF. The helper is renamed from i2c_mux_reg_probe_dt() to i2c_mux_reg_probe_fw() to reflect that. Accessor translation: of_parse_phandle("i2c-parent") + of_find_i2c_adapter_by_node() -> fwnode_find_reference() + i2c_find_adapter_by_fwnode() of_get_child_count() -> device_get_child_node_count() of_property_read_bool() -> device_property_read_bool() for_each_child_of_node() -> device_for_each_child_node() of_property_read_u32("reg") on ACPI device nodes: acpi_get_local_address() everything else (OF, swnode, ACPI data nodes): fwnode_property_read_u32() of_property_read_u32("idle-state") -> device_property_read_u32() The child-node branch uses is_acpi_device_node() rather than is_acpi_node(): the latter also matches ACPI data nodes (the _DSD hierarchical-property children used by PRP0001-style firmware), which have no ACPI handle and would make acpi_get_local_address() fall back to evaluating _ADR against the root namespace and return -ENODATA. Routing data nodes through fwnode_property_read_u32() instead lets them resolve the "reg" property the same way OF and swnode children do. Behavioural preservations (deliberate, to avoid regressing existing users): - The three-way endian fallback is kept verbatim: an explicit "little-endian" property wins, then "big-endian", and otherwise the host's compile-time byte order. device_is_big_endian() is not used here because it ignores "little-endian" and introduces "native-endian" semantics, which would diverge from the binding. - The "if (!mux->data.reg)" guard around devm_platform_get_and_ioremap_resource() in probe() is kept. drivers/platform/mellanox/mlx-platform.c registers i2c-mux-reg platform_devices with no memory resource and supplies a pre-set .reg / .reg_size through struct i2c_mux_reg_platform_data; without the guard those registrations would fail in probe(). - The "if (!mux->data.reg)" ioremap block (and the paired reg_size validation that depends on it) is hoisted above i2c_get_adapter(mux->data.parent), so the fwnode path preserves master's ordering of "ioremap before parent-adapter get". For platdata users the validation runs from a slightly earlier position, but mux->data.reg_size is already set from platdata by then, so the order is functionally neutral. The OF-only of_address_to_resource() translation in the old probe_dt() is dropped because the same address is available from the platform_device resource table on OF as well as ACPI, and the existing fallback in probe() ioremaps it. Acked-by: Peter Rosin Signed-off-by: Abdurrahman Hussain Assisted-by: Claude-Code:claude-opus-4-7 Assisted-by: sashiko:gemini-3.1-pro-preview Signed-off-by: Wolfram Sang Signed-off-by: Andi Shyti

i2c: Use named initializers for arrays of i2c_device_data

2026-06-04T23:09:25+00:00

While being less compact, using named initializers allows to more easily see which members of the structs are assigned which value without having to lookup the declaration of the struct. And it's also more robust against changes to the struct definition. The mentioned robustness is relevant for a planned change to struct i2c_device_id that replaces .driver_data by an anonymous union. While touching all these arrays, unify usage of whitespace in the list terminator. This patch doesn't modify the compiled arrays, only their representation in source form benefits. The former was confirmed with x86 and arm64 builds. Signed-off-by: Uwe Kleine-König (The Capable Hub) Reviewed-by: Wolfram Sang Link: https://lore.kernel.org/r/20260518164510.805502-2-u.kleine-koenig@baylibre.com Signed-off-by: Andi Shyti

i2c: muxes: pca954x: Fix broken reset-gpio usage

2025-11-03T17:04:15+00:00

Revert commit 690de2902dca ("i2c: muxes: pca954x: Use reset controller only") and its dependent commit 94c296776403 ("i2c: muxes: pca954x: Reset if (de)select fails") because the first breaks all users of the driver, by requiring a completely optional reset-gpio driver. These commits cause that mux driver simply stops working when optional reset-gpio is not included, but that reset-gpio is not pulled anyhow. Driver cannot remove legacy reset-gpios handling. Fixes: 690de2902dca ("i2c: muxes: pca954x: Use reset controller only") Signed-off-by: Krzysztof Kozlowski Signed-off-by: Wolfram Sang

i2c: mux: pca9541: Use I2C adapter timeout value for arbitration timeout

2025-09-12T22:19:18+00:00

Remove existing arbitration timeout macros and use I2C adapter timeout value for arbitration timeout and forceful bus ownership. I2C adapter timeout can be configurable from user space, so using it for arbitration timeout helps in configuring the arbitration timeout from user space depending on the use case. Signed-off-by: Manikanta Guntupalli Signed-off-by: Wolfram Sang

i2c: muxes: pca954x: Reset if (de)select fails

2025-08-11T18:10:09+00:00

If the channel selection or deselection times out, it indicates a failure in the mux's I2C subsystem. Without sending a reset pulse, a power-on-reset of the entire device would be required to restore communication. The datasheet specifies a minimum hold time of 4 ns for the reset pulse, but due to the path's capacitance and themux having its own clock, it is recommended to extend this to approximately 1 us. Since reset controller is used, there is no need to take care of other devices sharing the same reset line. Signed-off-by: Wojciech Siudy [wsa: removed superfluous prinout, unneeded braces and fixed indent] Signed-off-by: Wolfram Sang

i2c: muxes: pca954x: Use reset controller only

2025-08-11T18:09:54+00:00

Fallback to legacy reset-gpios is no more needed, because the framework can use reset-gpios properity now as well. Signed-off-by: Wojciech Siudy [wsa: fixed whitespace issue] Signed-off-by: Wolfram Sang

treewide: rename GPIO set callbacks back to their original names

2025-08-07T08:07:06+00:00

The conversion of all GPIO drivers to using the .set_rv() and .set_multiple_rv() callbacks from struct gpio_chip (which - unlike their predecessors - return an integer and allow the controller drivers to indicate failures to users) is now complete and the legacy ones have been removed. Rename the new callbacks back to their original names in one sweeping change. Signed-off-by: Bartosz Golaszewski

i2c: muxes: mule: Fix an error handling path in mule_i2c_mux_probe()

2025-08-03T20:47:57+00:00

If an error occurs in the loop that creates the device adapters, then a reference to 'dev' still needs to be released. Use for_each_child_of_node_scoped() to both fix the issue and save one line of code. Fixes: d0f8e97866bf ("i2c: muxes: add support for tsd,mule-i2c multiplexer") Signed-off-by: Christophe JAILLET Signed-off-by: Wolfram Sang

i2c: mux: pca954x: Use dev_fwnode()

2025-06-27T10:51:07+00:00

irq_domain_create_simple() takes fwnode as the first argument. It can be extracted from the struct device using dev_fwnode() helper instead of using of_node with of_fwnode_handle(). So use the dev_fwnode() helper. Signed-off-by: Jiri Slaby (SUSE) [wsa: proper commit header] Signed-off-by: Wolfram Sang

i2c: use inclusive callbacks in struct i2c_algorithm

2025-06-12T08:05:31+00:00

Convert the I2C subsystem to drop using the 'master_'-prefixed callbacks in favor of the simplified ones. Fix alignment of '=' while here. Signed-off-by: Wolfram Sang